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61.
Aida Karimi Seyed Hesam Mirfarsi Soosan Rowshanzamir Fatemeh Beyraghi Daniel Lester 《国际能源研究杂志》2020,44(11):8877-8891
Weak phase separation and vulnerable linking groups between aromatic units are common setbacks of sulfonated aromatic proton exchange membranes (PEMs) from durability point of view. In this study, sulfonated poly(ether ether ketone) (SPEEK) membranes were exposed to Fenton's solution for a specific time, ranging from 10 to 60 minutes. Chemical structure and morphology evolution, decay in mechanical and thermal stability, and H2 permeability of SPEEK membranes were evaluated during the chemical degradation. Less-entangled polymeric chains with lower average molecular weight of degraded SPEEK samples diminished mechanical rigidity. In addition, reduction of aromatic rings in each repeat unit led to higher thermal decomposition rate. Furthermore, randomly distributed micro-defects in the SPEEK morphology and an increase in water sorption can reduce the fatigue strength of membranes in the wet-dry cycles. Eventually, hydrogen cross-over rate was gradually increased, and henceforth, accelerated destructive radical formation and degradation can be predicted. 相似文献
62.
Mehrzad Arjmandi Mahdi Pourafshari Chenar Majid Peyravi Mohsen Jahanshahi 《应用聚合物科学杂志》2020,137(19):48672
Physical modification of support layers (SLs) for thin-film composite (TFC) forward osmosis (FO) membranes is the main goal of this study. Accordingly, the strategy of metal–organic framework (MOF)-based porous matrix membrane (PMM) was used for the fabrication of controllable SLs. Fourteen different TFC FO membranes were successfully fabricated by interfacial polymerization (IP) technique over the fourteen different SLs made of polyetherimide (PEI), polyethersulfone (PES), and twelve MOF-based PMM. The controllable MOF particles, fabricated SLs, and TFC membranes were characterized by Fourier-transform infrared spectroscopy (FTIR), powder X-ray diffraction (PXRD), dynamic light scattering (DLS), field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), contact angle (CA), inductively coupled plasma (ICP), and developed SHN1 method. The results showed that the PMM strategy can lead to an increase in the degree of crosslinking of polyamide (PA) as a result of physical modification of the original SLs. Also, the PMM strategy reduced the structural parameters and hence the internal concentration polarization (ICP) was controlled. However, according to the characteristic curve, physical modification of the structure of PES and PEI by MOF-based PMM strategy caused a small and dramatic effect (respectively) on the performance of the TFC FO membranes. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 137, 48672. 相似文献
63.
A series of sodium poly(styrene sulfonate)-block-poly(4-tert-butylstyrene) (NaPSS-b-PtBS) copolymers and related homopolymers were characterized by Fourier transform infrared (FT-IR) and nuclear magnetic resonance (NMR) spectroscopy. The homopolymers included polystyrene (PS), poly(4-tert-butylstyrene) (PtBS), sodium poly(4-styrene sulfonate) (NaP4SS), sodium poly(styrene sulfonate) (NaPSS) with various sulfonation levels, and partially sulfonated PtBS (PtBSS). The structures of NaPSS and PtBSS were elucidated, and the effect of sulfonation level on the NaPSS FT-IR spectrum was studied. The characteristic peaks for NaPSS and PtBSS in FT-IR and NMR spectra were identified. 相似文献
64.
Polyphosphazenes and metal phosphonates have offered better opportunities than other organoinorganic polymers as starting polymers for the synthesis of sulfonated derivatives. Sulfonated organic polymers are well established in many technological applications and are covered by several literature reviews. Organoinorganic sulfonated polymers are rather new and have never been considered as a self-standing class. Yet since ion-containing polymers and organoinorganic polymers are expanding research fields, organoinorganic sulfonated polymers are likely to attain more attention in the future. The present review therefore covers the synthesis, structure, and properties of sulfonated polyphosphazenes and sulfonated metal phosphonates, in order to indicate what may be expected from organoinorganic polymers functionalized in this fashion.Presented at the 1st Italian Workshop on Cyclo- and Polytphosphazenen Materials. February 15 16, 1996, at the CNR Research Area in Padova, Italy. 相似文献
65.
Compatibility of acidic (H), Na, and Zn neutralized sulfonated polystyrene ionomer blends with Poly(2,6-dimethyl- 1,4-phenylene
oxide) (PPO) and Poly(2,6-dichloro- 1,4-phenylene oxide) (PDCIPO) was investigated by Dilute Solution Viscometry (DSV) and
Differential Scanning Calorimetry (DSC). The intrinsic viscosities of the blends, are measured in suitable solvents. The degree
of compatibility of the blends is characterized by Δb parameter. According to the results, PPO is completely miscible, except
for Na-neutralized 1.7 mol% sulfonated polystyrene (Na1.7SPS) which is completely immiscible with PPO and PDClPO. PDClPO is
completely miscible with Zn-neutralized sulfonated polystyrene (Zn4.8SPS) and partially miscible with acid sulfonated polystyrene
(4.8SPS).
Received: 12 August 2001/Revised version: 21 January 2002/Accepted: 11 March 2003
Correspondence to Leyla Aras 相似文献
66.
Phase Inversion Strategy to Flexible Freestanding Electrode: Critical Coupling of Binders and Electrolytes for High Performance Li–S Battery
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Wandi Wahyudi Zhen Cao Pushpendra Kumar Mengliu Li Yingqiang Wu Mohammed N. Hedhili Thomas D. Anthopoulos Luigi Cavallo Lain‐Jong Li Jun Ming 《Advanced functional materials》2018,28(34)
Development of flexible and freestanding electrode is attracting great attention in lithium–sulfur (Li–S) batteries, but the severe capacity fading caused by the lithium polysulfides (PSs) shuttle effect remains challenging. Herein, a completely new polymeric binder of polyethersulfone is introduced. Not only it enables massive production of flexible/current‐free electrode by a novel concept of “phase‐inversion” approach but also the resultant polymeric networks can effectively trap the soluble polysulfides within the electrode, owing to the higher hydrophilicity and stronger affinity properties than the routine polyvinylidene fluoride. Coupling with polysulfide‐based electrolyte, the Li–S cell shows a higher capacity of 1141 mAh g?1, a lower polarization of 192 mV, and a more stable capacity retention with 100% Coulombic efficiency over 100 cycles at 0.25C. The advantages of favored binder and electrolyte are further demonstrated in lithium‐ion sulfur full battery with lithiated graphite anode, which demonstrates much improved performance than those previously reported. This work not only introduces a novel strategy for flexible freestanding electrodes but also enlightens the importance of coupling electrodes and electrolytes to higher performances for Li–S battery. 相似文献
67.
Broadband dielectric spectroscopy of Nafion‐117, sulfonated polysulfone (sPSF) and sulfonated polyether ketone (sPEK) membranes
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Wasim F. G. Saleha Rahul Ramesh Naresh Nalajala Arup Chakraborty Bradley P. Ladewig Manoj Neergat 《应用聚合物科学杂志》2017,134(18)
Nafion®‐117, sulfonated polysulfone (sPSF) and sulfonated polyetherketone (sPEK) are characterized using broadband dielectric spectroscopy in the frequency range of 10 MHz–100 mHz. Overall, there are 4–5 relaxation processes in these sulfonated membranes and a comparison of their spectral features allows assigning the relaxation processes. At an optimum amplitude of ~100 mVrms, all the relaxations are clearly defined as the electrode polarization is minimized. At low temperatures (?130 °C), these membranes show a broad relaxation peak in the mid‐frequency region, which quickly shifts towards the high‐frequency region as the temperature is increased to ?90 °C. This peak is observed in proton exchange membranes for the first time due to the use of low ac amplitude, and it is assigned to the relaxation of the confined water in the micro‐pores. With all the membranes, the peak associated with ? SO3H group relaxation is observed in the same frequency range at a temperature of ~?80 °C. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44790. 相似文献
68.
69.
以氧化煤与磺化聚苯乙烯高分子采用溶剂共混法 ,制成复合型功能性材料———煤基离子交换剂 .该材料主要用于对废水中重金属离子Zn2 +、Pb2 +、Cd2 +、Ni2 +的处理 ,吸附效果具有独特性 ,是新型的煤基高分子材料 ,在煤的非能源利用方面开辟了新的途径 相似文献
70.
聚醚砜改性的E-44/DDM胶粘剂葛建芳(广东石油化工专科学校茂名525000)[摘要]本文介绍了经聚醚砜(PES)改性的E-44/DDM胶粘剂的粘接性能及相态结构。[关键词]环氧树脂;聚醚砜;改性E-44/DDMAdhesiveModifiedb... 相似文献